A neonate (male), delivered vaginally at term is diagnosed with sickle cell disease by neonatal examination and testing. On the basis of this diagnosis, the most suitable initial step is the administration of which of the following?

Erythromycin Hydroxyurea Oxygen Penicillin *This patient case is from the Docplexus Editorial Team for educative purposes only. (The correct answer is posted in the comment section below!)